I need a phone to keep in the car since I sometimes forget my phone at home. However, I'd like to get a smartphone (obviously one based on Android since I'm posting here ) but it seems most carriers require expensive monthly recurring voice/date plans if you opt to use a smartphone. I'm fine with paying full price for the phone but since this will be, in essence, an emergency phone (albeit a very nice, full-featured one), it'll likely see very little use and I'd like to keep the annual costs down to a minimum. I thought my only option was AT&T (LG Thrive + $0.10/min Pay As You Go plan, ~$100/year) but then I noticed posts here mentioning per day 3G data usage which sounds even better than the monthly $5~25 data packages AT&T offers. I guess my question is, will the Nexus S i9020t or Nexus One work with T-Mobile Pay As You Go on 3G? Also, how does that day pass thing work? Regardless of whether I go with T-Mobile or AT&T, I plan on buying a $100 prepaid card (which should be good for a year) and just refilling when the credit runs out or right before it expires in a year, whichever comes first. Thanks!